The only unbeaten team in the Bowl Subdivision, the Hoosiers were an easy pick after beating the Buckeyes 13-10 in the Big Ten championship game.
Ohio State drops two spots to No. 3. Georgia steps up one spot to No. 2 after claiming the SEC championship against Alabama, which dropped two spots to No. 12.
While they landed firmly in the College Football Playoff field, in the re-rank the Crimson Tide trail No. 9 Notre Dame and No. 11 Brigham Young.
Several teams made multiple-spot jumps after conference championship weekend, led by No. 4 Texas Tech. The Red Raiders climbed two after beating Brigham Young for the second time and bumped No. 5 Oregon, No. 6 Texas A&M and No. 7 Mississippi down one.
Also climbing are No. 10 Miami, No. 17 James Madison, No. 32 Boise State, No. 34 Duke, No. 47 Kennesaw State and No. 53 Western Michigan.
The final top 25 of the regular season includes eight teams from the SEC, six teams from the Big Ten, four from the Big 12, two from the ACC and then Notre Dame and four teams from the Group of Five in No. 15 Tulane, JMU, No. 22 North Texas and No. 23 Navy.
There will be one last re-rank after the national champion is crowned in January.